The subject invention concerns a method of erecting a foundation structure for a building substructure.
In erecting concrete building substructures, in situ casting is the procedure most commonly used today. The use of finished, prefabricated beams that are delivered to the building site, is justified only when the building project is a large one and the resources in terms of economy, machinery and personnel are ample from the start. Otherwise, i.e. in the case of building projects of small or medium size, the use of such beams involves highly specialized equipment, such as specialty vehicles, to transport the beams to the building site and, on the building site, hoisting cranes having a considerable lifting capacity, all of which is considered to be too expensive.
Also in situ casting, however, involves working processes that are complicated in several respects but have long been used, in the absence of better alternatives. For instance, following the excavation to accommodate the the building substructure, and deposition of a bed of gravel or macadam, a team of carpenters is called upon to set out and erect on the bed the forms necessary for the casting of the foundation beams. After completion of the casting operation and setting of the concrete, the team of carpenters has to return to the building site to remove the beam forms. Very often, the dismantled forms cannot be re-used. Some of the casting costs thus are consumed by the used-up form timber. An added complication is that workers of several different categories, such as excavator operators, carpenters, and concrete casters, must intervene alternatingly in the working process. The risk for unnecessary delays thus is considerable, resulting in increased costs.
In accordance with the teachings of the invention a method has been developed by means of which the work involved in erecting a foundation structure for a building substructure is highly facilitated.